The printer has hitherto been well known which places on the recording paper the transfer tape coated with a thermalmeltable transfer agent and heats the transfer agent from the back of the tape by means of the thermal head to stick and transfer the agent onto the recording paper. Such printer as shown in FIG. 1 has hitherto been used.
Explanation in brief will be given on the above construction in accordance with FIG. 1, in which at both sides of a base 201 are erected side plates 202 and 203 for mounting thereto various members to be discussed below. A carriage 204 is mounted to a guide shaft 205 slidably in parallel to a platen shaft 206, and has at the center a thermal head 208 and at both sides thereof guide rollers 211 for press-contacting a transfer tape 109 onto a recording paper 10, so that a tape cassette 212 is adapted to be mounted on the carriage 204 and provides a tape supply spool 214 and a tape take-up spool 215 laterally juxtaposed and forms a vacancy for containing therein the thermal head 208 and guide rollers 211, the vacancy being of a recess 212a formed between both the spools 214 and 215 and at the platen 206.
The transfer tape 109 drawn out from the supply spool 214 is inserted between the recording paper 10 and the thermal head 208 and then wound onto the take-up spool 215.
The carriage 204 operates to wind the tape 109 and move step by step at every printing by means of a drive belt 217 driven through pulleys 216 by a drive motor (not shown), and, during the return of carriage 204, is slightly raised by a plunger 219 through a lever (not shown) to move the thermal head 208 away from the recording paper 10, thereby returning to the beginning of the line.
A feed roller 220 carries out line spacing of recording paper 10 by a pulse motor 221.
Rollers 222 are fitted rotatably onto a shaft 223 and for holding the paper 10. Such conventional construction has been defective in the following points:
(a) The tape cassette 212 and carriage 204 therefor are disposed in parallel to the base 201, in other words, in the horizontal plane, whereby the printer as a whole expands in depth by longitudinal dimension of carriage 204; PA1 (b) The carriage 204 requires a space through which it moves in parallel with respect to the platen shaft 206, thereby reducing to that extent the space for housing the necessary mechanism; PA1 (c) Since the thermal head 208 is disposed between both the spools 214 and 215 in the tape cassette 212, spaces for moving the carriage 204 should be insured also at both outsides of the maximum printing width, thereby enlarging the printer in lengthwise length to an extent of moving dimension of carriage 204; PA1 (d) Also, in the driving system, every printing requires winding-up of tape 109 and movement of carriage 204 in a stepped manner, thereby inevitably requiring an increase in power consumption and the use of a drive motor of large rated output. Such need of large power consumption has made it impossible to materialize a portable printer driven by batteries; and PA1 (e) Generally, upon peeling off the transfer tape 109 from the paper 10 while the transfer agent is still molten just after printing, the dotted portions come out to deteriorate the printing quality. Therefore, for the aforesaid mechanism which winds up the transfer tape 109 at every printing, the tape 109 should be peeled or wound up after a certain time from printing, which inevitably restricts the printing speed to some extent, resulting in that the printing at high speed has been impossible.